Comparison of SGLT2 inhibitors vs. DPP4 inhibitors for patients with metabolic dysfunction associated fatty liver disease and diabetes mellitus.

PURPOSE: This study aimed to examine the potential benefit of sodium-glucose cotransporter 2 (SGLT2) inhibitors for patients with metabolic dysfunction-associated fatty liver disease (MAFLD) and diabetes mellitus (DM) using a real-world database. METHODS: We analyzed individuals with MAFLD and DM newly initiated on SGLT2 or dipeptidyl peptidase 4 (DPP4) inhibitors from a large-scale administrative claims database. The primary outcome was the change in the fatty liver index (FLI) assessed using a linear mixed-effects model from the initiation of SGLT2 or DPP4 inhibitors. A propensity score-matching algorithm was used to compare the change in FLI among SGLT2 and DPP4 inhibitors. RESULTS: After propensity score matching, 6547 well-balanced pairs of SGLT2 and 6547 DPP4 inhibitor users were created. SGLT2 inhibitor use was associated with a greater decline in FLI than DPP4 inhibitor use (difference at 1-year measurement, - 3.8 [95% CI - 4.7 to - 3.0]). The advantage of SGLT2 inhibitor use over DPP4 inhibitor use for improvement in FLI was consistent across subgroups. The relationship between SGLT2 inhibitors and amelioration of FLI was comparable between individual SGLT2 inhibitors. CONCLUSIONS: Our analysis using large-scale real-world data demonstrated the potential advantage of SGLT2 inhibitors over DPP4 inhibitors in patients with MAFLD and DM.

Pseudo-outbreak of Mycobacterium paragordonae in a hospital: possible role of the aerator/rectifier connected to the faucet of the water supply system.

BACKGROUND: Pseudo-outbreaks of non-tuberculous mycobacteria (NTM) in association with the water supply system in hospitals have been previously reported. We found that the frequency of NTM isolation in clinical samples increased after the reconstruction and renovation of a hospital in Japan in 2014. AIM: To analyse NTM, their possible relationship with the hospital water supply system, and outcomes of preventive measures. METHODS: Environmental samples obtained from the water supply in hospital wards were tested for NTM. On obtaining positive results, the bacteria were further analysed using polymerase chain reaction (PCR). FINDINGS: The PCR products of NTM showed that most samples tested positive for Mycobacterium paragordonae. Because none of the analysed patients developed any disease due to these bacteria, this event was considered a pseudo-outbreak. Investigation of the water supply system revealed that samples obtained from the recently attached aerators/rectifiers during hospital renovation tested positive for these bacteria. Therefore, measures to remove aerators/rectifiers and prevent patients from drinking tap water in the hospital were introduced. Thereafter, the frequency of NTM-positive samples significantly decreased in the hospital. CONCLUSION: This study is one of the few reports which reveal the possibility of pseudo-outbreaks of M. paragordonae in hospitals, hence raising the question whether aerators/rectifiers should be used in hospitals at all, because their mesh structure may promote NTM proliferation in supplied water. The importance of surveillance of bacteria derived from the environment, particularly after hospital reconstruction/renovation, is re-emphasized.

Peripartum type B aortic dissection in patients with Marfan syndrome who underwent aortic root replacement: a case series study.

OBJECTIVE: To investigate pregnancy outcomes, especially the risk of pregnancy-related aortic dissection (AD), in patients with Marfan syndrome (MFS) after prophylactic aortic root replacement (ARR). DESIGN: Retrospective case series study. SETTING: Tertiary perinatal care centre at a university hospital. POPULATION: Pregnant women fulfilling the revised Ghent nosology (2010) criteria for MFS who were managed at our institute. METHODS: The pregnancy outcomes of all patients with MFS managed at our institute between 1982 and September 2016 were reviewed retrospectively based on medical records. MAIN OUTCOME MEASURES: Obstetrical management and complication including the incidence of AD throughout the peripartum period. RESULTS: Among 22 patients (28 pregnancies) who had been managed as potential MFS or related disorders, 14 (17 pregnancies) fulfilled the revised Ghent nosology (2010) criteria for MFS and were enrolled in this study. Five patients (five pregnancies) had received ARR before conception: three (60%) developed type B aortic dissection [AD(B)] during the peripartum period, compared with only one of 10 patients (12 pregnancies) without ARR (P < 0.05, Chi-square test). CONCLUSIONS: Our study results suggest that MFS patients after prophylactic ARR are still at high risk of AD(B) during the peripartum period. Careful pre-pregnancy counselling and multidisciplinary care throughout the peripartum period are essential for the management of MFS, even after surgical repair of an ascending aortic aneurysm. TWEETABLE ABSTRACT: MFS patients after prophylactic ARR are still at high risk of type B aortic dissection during the peripartum period.

Characterization of porcine sapelovirus isolated from Japanese swine with PLC/PRF/5 cells.

Porcine sapelovirus (PSV) is a causative agent of neurological disorders, fertility disorders and dermal lesions of swine. In this study, we isolated two PSV strains, Jpsv477 and Jpsv1315, from swine faecal specimens using a PLC/PRF/5 cell culture system. The PSV infection of PLC/PRF/5 cells induced a cytopathic effect (CPE). Two types of virus particles with identical diameter (~35 nm) but different densities (1.300 and 1.285 g/cm3 ) were observed in the cell culture supernatants. Analysis of the entire genome sequence of Jpsv477 and Jpsv1315 revealed that both strains possess 7,558 nucleotides and the poly (A) tail and have a typical PSV genome organization consisting of a 5' terminal untranslated region (5'UTR), a large open reading frame (ORF), and a 3' terminal untranslated region (3'UTR). The ORF encodes a single polyprotein that is subsequently processed into a leader protein (L), four structural proteins (VP1, VP2, VP3 and VP4) and seven functional proteins (2A, 2B, 2C, 3A, 3B, 3C and 3D). The structural proteins VP1, VP2, VP3 and VP4 have molecular masses of ~35, ~26, ~25 and ~6 kDa. The N-terminal amino acid sequence analysis of VP1, VP2, VP3 and VP4 confirmed that the cleavage sites between VP4 and VP2, VP2 and VP3, and VP3 and VP1 are K/A, Q/G and Q/G, respectively. We further confirmed that HepG2/C3A, Vero E6 and primary green monkey kidney cells (PGMKC) were also susceptible to PSV infection. The stability assay demonstrated that PSV was inactivated by heating at 60°C for 10 min or 65°C for 5 min. The virus also lost infectivity by incubation with 62.5 ppm of NaClO for 30 min.

Distribution of norovirus genotypes and subtypes in river water by ultra-deep sequencing-based analysis.

To determine the distribution of Norovirus (NoV) genotypes in natural river water in Thailand, we conducted a genome analysis using a next-generation sequencer. Twenty-five river water samples were collected at five different sites of the Khlong Klon River in the suburbs of Bangkok between August 2013 and December 2014. The partial genome of NoV was detected in 15 of the 25 samples (60·0%). Seven of these 15 samples (46·7%) contained multiple NoV GII genotypes: GII.4, GII.6, and GII.17. Our data showed that GII.17 had already emerged in August 2013 as a minor population, and it became a major genotype in December 2014. Our findings indicate that the virus was likely to have been circulating in the community before it appeared in the river water. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study was to investigate the frequencies of multiple genogroups and genotypes of norovirus in the river water near Bangkok, Thailand, by ultra-deep sequencing-based analysis. This study revealed that the epidemic strain was likely to have been circulating in the community before it appeared in the river water. Monitoring of the Norovirus (NoV) genomes in the natural environment may contribute to an understanding of the emergence of new epidemic NoV strains in human populations.

Skin pigmentation is inversely associated with insulin resistance in healthy Japanese women.

AIM: As a low-pigment skin type is prevalent in men and women with type 1 diabetes, it is possible that skin pigmentation may be associated with insulin resistance. This study aimed to cross-sectionally examine this association in healthy women. METHODS: Study participants were 792 Japanese women who attended a health examination and were not taking any medication for diabetes. Skin pigmentation on the inner upper and lower arms and forehead was measured using a Mexameter® skin colorimeter, a narrow-band reflective spectrophotometer. Data are expressed as a melanin index, which quantifies melanin content. Fasting blood glucose and insulin levels were also measured, and homoeostasis model assessment for insulin resistance (HOMA-IR) scores were calculated. Information on medical history and lifestyle factors were obtained by a self-administered questionnaire, while data on sun exposure were collected through interviews. Plasma 25-hydroxyvitamin D levels were measured in a subsample of women (n=464). RESULTS: Melanin indices at the inner upper and lower arms were significantly and inversely associated with fasting insulin levels and HOMA-IR after controlling for age, body mass index, smoking status, indicators for rater effects, cumulative sun exposure and season at the time of measurement. Additional adjustment for plasma 25-hydroxyvitamin D levels did not alter the results. CONCLUSION: These data suggest that skin pigmentation is associated with insulin resistance, and encourage future studies into the potential role of melanin and related factors in glucose homoeostasis.

Molecular detection and characterization of noroviruses in river water in Thailand.

UNLABELLED: Norovirus (NoV) generally exists as a mixture of multiple genotype variants in nature. However, there has been no published report monitoring NoV in natural settings in Thailand. To obtain information on mixed presence of the NoV RNA genome, we conducted viral genome analysis of 15 water specimens collected from five sites in a river near Bangkok between August 2013 and August 2014. The number of viral RNA copies per specimen declined progressively from the most upstream to the most downstream site. Following direct nucleotide sequencing of the PCR products, we obtained three partial genome sequences of the NoV GI strain and 13 partial genome sequences of the NoV GII strains. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 outbreaks. On the other hand, only GI.4 was observed from the specimens collected on April, 2014. These results indicated that multiple genogroups and genotypes of noroviruses are present and are circulating in the natural environment in Thailand as in other countries. Our study provides comprehensive information on the occurrence of new variants. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study is the first paper that multiple genogroups and genotypes of norovirus exist, and are circulating in the river water near Bangkok, Thailand. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 that caused outbreaks in the world. Continued research will be essential for understanding the natural history of NoV and the control of future outbreaks.

A two-step hybrid technique for accurately localizing acoustic source in anisotropic structures without knowing their material properties.

Acoustic source localization techniques generally assume straight line propagation of waves from the acoustic source to the sensor. However, it is well-known that in anisotropic plates the acoustic energy does not always propagate in straight lines. Even for isotropic plates containing a cavity or an inclusion between the acoustic source and the sensor the straight line propagation assumption is violated. In such cases only options available in localizing acoustic source is to use relatively expensive distributed sensor systems, or to follow time reversal techniques based on the impulse response functions which is labor intensive and computationally demanding. A two-step hybrid technique is proposed in this paper for predicting acoustic source in anisotropic plates. During the first step it was assumed that the waves propagated along straight lines from the acoustic source to the sensor. The source was localized with this simplifying assumption. Then this first prediction was improved in the second step by solving an optimization problem. Experimental results showed that the second step always moved the estimates towards the actual source location. Thus it always reduced the prediction error irrespective of whether the final prediction coincided with the actual source location or not.

Occurrence of hepatitis E virus infection in acute hepatitis in Thailand.

Hepatitis E virus (HEV) infection is one of the enterically transmitted types of hepatitis. The present study was undertaken to estimate the occurrence of HEV infection in sporadic acute hepatitis in Thailand. Serum samples were obtained from 614 suspected acute hepatitis patients at two large hospitals in Bangkok during 2008, 2009, and 2011. Acute hepatitis E was identified by the presence of anti-HEV IgM (4.8%) using indirect ELISA kits and/or HEV RNA (4.5%) by a semi-nested reverse transcription-polymerase chain reaction assay. HEV IgM was the most common marker for detection (77%) at diagnosis, either by positive HEV IgM alone or together with HEV RNA, whereas HEV RNA alone was detected in 23% of patients. Overall, 4.2% of cases (26 out of 614) were acute HEV infection with the highest attack rate in the elderly age group. In addition, nucleotide sequence analysis of five HEV samples revealed 92.8-99.8% homology. All viruses were clustered into HEV genotype 3 and were similar genetically to swine HEV strains previously detected in the same area. Therefore, the occurrence of HEV infection with closely related to swine genotype 3 was approximately 4-5% of acute hepatitis cases in Thailand. Anti-HEV IgM was the most common marker at diagnosis.

Magnetic phase diagram of clathrate compound Ce3Pd20Si6 with quadrupolar ordering.

We present results of specific heat measurements on a Ce3Pd20Si6 single crystal and construct the magnetic phase diagram for the three cubic principal directions [100], [110] and [111]. The highly anisotropic phase diagram is discussed and can be qualitatively explained by the Zeeman splitting at the 8c-site. For B â€– [100], the present study found two different quadrupolar ordered phases, which meet the paramagnetic phase at a tri-critical point and establish the new phase boundaries.

Treatment for hypergranulation at gastrostomy sites with sprinkling salt in paediatric patients.

OBJECTIVE: To estimate the efficacy of sprinkling salt treatment (SS) of hypergranulation at gastrostomy sites in paediatric patients. METHOD: A prospective case-series study of paediatric patients with hypergranulation at gastrostomy sites. About one-third of a 5ml-teaspoon of table salt was sprinkled over the tissue once a day, either by the doctors/nurses in the wards or doctors in the outpatient setting. Treatment was continued by the patients or carers in the home, until the hypergranulation was seen to flatten. The patients were followed up by health professionals once a month. RESULTS: Eight paediatric patients (seven females and one male) were included in the study. The hypergranulation decreased in size and became almost flat in all patients within 3 days to 2 months (median 7 days). Five patients had a recurrence of hypergranulation, but were treated successfully by repeated SS. Skin erosion was observed in one patient when SS was continued too long; therefore, the treatment protocol was altered so that the salt was irrigated 10 minutes after SS. A biopsy of the hypergranulation tissue was taken from a patient and salt was sprinkled on the tissue in a dish to simulate SS for histopathological examination. Histopathologically, hypergranulation treated by SS exhibited reduced interstitial oedema. CONCLUSION: The results of this study suggest that hypertonic environment induced by SS effectively reduced the oedematous hypergranulation tissue. SS is advantageous over traditional treatment such as silver nitrate in that SS is inexpensive and can be continued by the parents and repeated if necessary at home.

Identification of Hic-5 as a novel regulatory factor for integrin αIIbß3 activation and platelet aggregation in mice.

BACKGROUND: Integrin αIIbß3 plays key roles in platelet aggregation and subsequent thrombus formation. Hydrogen peroxide-inducible clone-5 (Hic-5), a member of the paxillin family, serves as a focal adhesion adaptor protein associated with αIIbß3 at its cytoplasmic strand. OBJECTIVES: Hic-5 function in αIIbß3 activation and subsequent platelet aggregation remains unknown. To address this question, platelets from Hic-5(-/-) mice were analyzed. METHODS AND RESULTS: Hic-5(-/-) mice displayed a significant hemostatic defect and resistance to thromboembolism, which were explained in part by weaker thrombin-induced aggregation in Hic-5(-/-) platelets. Mechanistically, Hic-5(-/-) platelets showed limited activation of αIIbß3 upon thrombin treatment. Morphological alteration in Hic-5(-/-) platelets after thrombin stimulation on fibrinogen plates was also limited. As a direct consequence, the quantity of actin co-immunoprecipitating with the activated αIIbß3 was smaller in Hic-5(-/-) platelets than in wild-type platelets. CONCLUSION: We identified Hic-5 as a novel and specific regulatory factor for thrombin-induced αIIbß3 activation and subsequent platelet aggregation in mice.

Rapid screening method for quinolone residues in livestock and fishery products using immobilised metal chelate affinity chromatographic clean-up and liquid chromatography-fluorescence detection.

An efficient LC method was developed for screening the presence of quinolones (QLs)--comprising fluoroquinolones (FQs) and acidic quinolones (AQs)--residues in various livestock and fishery products. Targeted analytes were for nine FQs of marbofloxacin (MAR), ofloxacin (OFL), norfloxacin (NOR), ciprofloxacin (CIP), enrofloxacin (ENR), danofloxacin (DAN), orbifloxacin (ORB), difloxacin (DIF) and sarafloxacin (SAR), and three AQs of oxolinic acid (OXA), nalidixic acid (NAL) and flumequine (FMQ). Samples comprised ten different food products covering five matrices: muscle (cattle, swine and chicken), liver (chicken), raw fish (shrimp and salmon), egg (chicken), and processed food (ham, sausage and fish sausage). This method involved a simple extraction with (1:1) acetonitrile-methanol, a highly selective clean-up with an immobilised metal chelate affinity column charged with Fe(3+), a fast isocratic LC analysis using a short column (20 mm × 4.6 mm, 3 µm) with a mobile phase of (15:85:0.1) methanol/water/formic acid, and fluorescence detection (excitation/emission wavelengths of 295 nm/455 nm for FQs (495 nm for MAR), and 320 nm/365 nm for AQs). Among FQs, pairs of NOR/OFL, ORB/DIF and ENR/DAN were incompletely resolved. A confirmatory LC run with a Mg(2+) containing methanolic mobile phase was also proposed for the samples suspected of being positive. The optimised method gave satisfactory recoveries of 88.5% (56.1-108.6%) and 78.7% (44.1-99.5%) for intra- and inter-day assays with relative standard deviations of 7.2% (0.7-18.4%) and 6.8% (1.4-16.6%), respectively. Limits of quantitation ranged from 0.8 µg kg(-1) (DAN) to 6.5 µg kg(-1) (SAR). This method was successfully employed to analyse 113 real samples and two positive samples were found: fish sausage (CIP 990 µg kg(-1)) and shrimp (ENR 20 µg kg(-1)).

Interferon-gamma release assay for diagnosing Mycobacterium tuberculosis infections in patients with systemic lupus erythematosus.

Our aim was to analyze the performance of an interferon-gamma release assay, QuantiFERON-TB Gold (QFT-2G), for diagnosing Mycobacterium tuberculosis (MTB) infection in patients with systemic lupus erythematosus (SLE). We performed the QFT-2G and tuberculin skin test (TST) in 71 SLE patients. The QFT-2G results of 279 patients with other connective tissue diseases (CTD) and 35 healthy controls were analyzed. Of the 71 SLE patients, two (2.8%) were positive and 46 (64.8%) were negative by QFT-2G. All SLE patients had no evidence of active MTB infection, apart from one. QFT-2G produced a significantly higher number of indeterminate results in patients with SLE (23/71, 32.4%) compared with those with other CTD (5.7%) or healthy controls (0%) (p < 0.0001 and p < 0.0001). Decreased lymphocyte counts and high SLEDAI scores in SLE patients were shown to be risk factors for indeterminate results by multivariate analysis (p = 0.02 and p = 0.04). Among all patients with CTD, SLE itself and lymphocytopenia were found to be independent risks for indeterminate results (p = 0.00000625 and p = 0.000107). In conclusion, QFT-2G may have more potential to assist in the diagnosis of active and latent MTB infection than TST in SLE patients. However, because of the high frequency of indeterminate results, caution must be used when interpreting the results of QFT-2G among SLE patients, especially those who have parallel or subsequent flares.

Genetic diversity of genogroup IV noroviruses in wastewater in Japan.

AIMS: To investigate the prevalence, seasonality and genetic diversity of genogroup IV noroviruses (GIV NoVs) in wastewater in Japan. METHODS AND RESULTS: Untreated and treated wastewater samples were collected monthly for a year from a wastewater treatment plant in Japan. The concentrated wastewater samples were examined for the presence of GIV NoV genomes with seminested RT-PCR assay targeting partial capsid gene. Among 12 untreated and 12 treated wastewater samples tested, GIV NoV genomes were detected in three (25%) untreated and two (17%) treated wastewater samples with a high positive ratio in winter season. Genetic analysis revealed that the GIV NoVs in the wastewater samples were genetically diverse and were classified into three different genetic clusters. CONCLUSIONS: Frequent detection of GIV NoVs in winter season, which is a common epidemic period of human NoVs in Japan, indicates that GIV NoVs exhibit temporal trends similar to GI and GII NoVs. Based on the partial capsid gene sequences, we identified several unique GIV NoV strains belonging to the novel genetic cluster, demonstrating that GIV NoVs are more genetically diverse than previously appreciated. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings provide novel evidence of considerable genetic diversity among the GIV NoV strains.

Formation of chlorinated aromatics in model fly ashes using various copper compounds.

Various copper compounds found in fly ash are related to the formation of chlorinated aromatics. The formation potentials of chlorinated aromatics in different model fly ashes containing various copper compounds and the chemical behavior of such copper compounds were investigated. In model fly ash with copper metal, hydroxide, carbonate, or oxides, the generated amounts of chlorobenzene (CBz) and polychlorinated biphenyls (PCBs) and the average chlorination numbers were low and at the same level, respectively. The maximum generated amounts of chlorinated aromatics were observed at 300 degrees C. Although X-ray absorption near edge structure (XANES) spectra indicated that the chemical form of copper compounds changed little, they were found to promote the formation of chlorinated aromatics. Therefore, these copper compounds play the same role as CuO. On the other hand, in model fly ash with copper chloride, the generated amounts of CBz and PCBs were quite high and the average chlorination numbers was high. Dynamic changes were observed in XANES spectra, and the pre-edge peak attributed to monovalent copper compounds appeared at around 300 degrees C. A large difference was observed between these two groups in the amount of CuCl generated and the homologs of chlorinated aromatics present, indicating that CuCl played an important role in the formation of chlorinated aromatics.

Behaviour and adsorptive removal of siloxanes in sewage sludge biogas.

We investigated the behaviour of siloxanes, which adversely affect biogas engines, as well as their concentration levels in sewage sludge biogas in Japan. We also performed experiments on the absorptive removal of siloxanes using various adsorbents and determined the main adsorbent characteristics required for the removal of siloxanes. The results of our study on the concentration and composition of siloxanes in biogas were similar to previous reports. Moreover, we found that the concentration of siloxanes changes in relation to the outside air temperature based on real-time measurements of siloxanes using a continuous analyser. We further speculated that the continuous analyser would accurately indicate the siloxane concentration in model biogas but overestimate the siloxane concentration in actual biogas because of positive interference by VOCs and other biogas components. In the siloxane adsorption experiment, the equilibrium uptake of both cyclic siloxanes, D4 and D5, was positively related to the BET-specific surface area of the adsorbents and the fraction of the external surface area taken up by relatively large diameter pores. We attributed the adsorption results to the fact that the siloxane molecules are generally larger than micropores; therefore, they are less susceptible to adsorption to micropores. Based on these results, we concluded that adsorbents with large BET-specific surface areas, especially those with a high external specific surface area and pores of relatively large diameters, are desired for the removal of siloxanes.

Metabolic syndrome as a risk factor for high-ocular tension.

OBJECTIVE: To investigate the relationship between the metabolic syndrome and intraocular pressure (IOP). METHODS: An observational study was conducted in a medical health checkup program at a general hospital. This study involved 14 003 apparently healthy Japanese men and women, 18-83 years of age, with a mean IOP of 14.8 (3.0) mm Hg. IOP was examined by noncontact tonometer. High-ocular tension was defined as IOP >21 mm Hg without optic-disc abnormalities or history of receiving any anti-glaucoma therapy. Modified criteria of the revised National Cholesterol Education Program Adult Treatment Panel III (rATPIII), the new International Diabetes Federation definition, and the Japan Society for The Study of Obesity definition were used to characterize the metabolic syndrome. Air temperature was assessed from the Gifu Meteorological Observatory, Gifu, Japan. RESULTS: In the male and female subjects, mean IOP and the prevalence of high-ocular tension became high in direct correlation with the increased number of metabolic syndrome components. To analyze by logistic regression, the metabolic syndrome defined by rATPIII was positively and maximum temperature was negatively correlated with high-ocular tension in males (adjusted odds ratio: 2.0 [95% confidence interval, CI, 1.43-2.78] and 0.63 [95% CI, 0.54-0.73], respectively) and in females (adjusted odds ratio: 7.09 [95% CI, 3.74-13.43] and 0.67 [95% CI, 0.53-0.87], respectively). Three of five metabolic syndrome components (fasting plasma glucose, blood pressure, and triglycerides) were related to high-ocular tension. CONCLUSION: The metabolic syndrome is a risk factor for high-ocular tension.

Innervation of histamine neurons in the caudal part of the arcuate nucleus of hypothalamus and their activation in response to food deprivation under scheduled feeding.

It has been well established that histaminergic neurons innervate densely the anterior hypothalamus and regulate several functions through the histamine H1 receptor (H1R). However, the physiological function of the histaminergic neurons in other regions including the posterior hypothalamus has not been fully investigated. Recently, we have found a selective c-Fos expression in the caudal part of the arcuate nucleus of the hypothalamus (cARC) by food deprivation under scheduled feeding in rats. In this study, we histochemically examined the correlation of this c-Fos expression with the activation of histaminergic neurons in this region using an anti-H1R antibody. Strong H1R immunoreactivity was observed in the perikarya of the c-Fos positive cells. Abundant histamine-containing fibers were also found in the cARC and in the area between the cARC and the tuberomammillary nucleus (TM), where the histaminergic neuronal cell bodies are exclusively distributed. Our morphological observations suggest that c-Fos expression in the cARC by food deprivation under scheduled feeding is caused by the activation of histaminergic neurons projected from the TM.